Spacer



FIG. 1 is a isometric view of the spacer of the present design;

FIG. 2 is a top plan view of the design shown in FIG. 1, the bottom plan view being a mirror image thereof; and,

FIG. 3 is a front elevational view of the design shown in FIG. 1, the rear elevational view being a mirror image thereof. 

The ornamental design for a spacer, as shown and described. 